The GEARWRENCH Bolt Biter Extraction Sockets are available in sets of eight, 15, and 28 for use with 1/4" and 3/8" drives. The tapered flute design allows the sockets on and off of rusted or worn fasteners. The Bolt Biter features minus-size sockets to grip worn fasteners that can no longer be gripped by traditional sizes. Its bidirectional design can also tighten or re-use a damaged fastener as well, making it ideal for specialized components. Bolt Biter grips rusted or rounded fasteners instead of cutting into them, allowing the sockets to last longer when used with an impact gun in addition to ratchets, wrenches, or pliers. The sockets have a black oxide finish to resist corrosion and come with a lifetime warranty.